let div = document.getElementById('container');
let boxs = [];
for (let i = 0; i < 10; i++) {
	let box = new Box(div);
	boxs.push(box);
}
setInterval(function() {
	for (let i = 0; i < boxs.length; i++) {
		boxs[i].randomXy();
		boxs[i].randomColor();
	}
}, 2000);